TWI632782B - System and method for testing radio frequency wireless signal transceivers using wireless test signals - Google Patents

Abstract

A system and method for facilitating wireless testing of a radio frequency (RF) signal transceiver device under test (DUT). Multiple radio frequency (RF) test signals generated from radio frequency (RF) test signals radiated from the device under test (DUT) can be captured using multiple antennas located within a shielded enclosure containing the device under test (DUT) And causing their individual signal phases to be controlled according to one or more signal characteristics, including ones of their individual signal power levels, the individual signal phases when they are received, and one of the received signals A combined signal power level. The phase control of the captured radio frequency (RF) test signal can be performed individually for any tested device under test (DUT) located within the shielded enclosure, thereby providing for the shielded enclosure to be unrelated to the device under test (DUT) The multipath signal environment is placed and compensated, and a wired test signal path is simulated in the wireless test of the device under test (DUT).

Description

System and method for testing radio frequency wireless signal transceiver using wireless test signal

This invention relates to testing radio frequency (RF) wireless signal transceivers, and in particular to testing such devices without the use of RF signal cables carrying RF test signals.

Related application

This application is a continuation of U.S. Patent Application Serial No. 13/839,162, filed on March 15, 2013, entitled "System and Method for Testing Using Wireless Test Signals to Test RF Wireless Signal Transceivers" Radio Frequency Wireless Signal Transceivers Using Wireless Test Signals), and a continuation of the US Patent Application No. 13/839,583, filed on March 15, 2013, entitled "Using Wireless Test Signals to Test Radio Frequency Wireless" System and Method for Testing Radio Frequency Wireless Signal Transceivers Using Wireless Test Signals, the entire disclosures of which are incorporated herein by reference.

Many modern electronic devices use wireless technology for both connection and communication purposes. Because wireless devices transmit and receive electromagnetic energy, and because two or more wireless devices may interfere with each other's operation due to their signal frequency and power spectral density, these devices and their wireless technologies must adhere to various wireless technology standard specifications.

When designing such devices, engineers must pay extra attention to ensure that such devices meet or exceed each of the wireless technology they specify to comply with standards-based specifications. Furthermore, when these devices are manufactured in large quantities in the future, they will be tested to ensure that manufacturing defects do not result in improper operation, including whether they comply with the standards of the included wireless technology based standards.

In order to test these devices after they are manufactured and assembled, current wireless device test systems ("testers") utilize a subsystem to analyze signals received from each device. The subsystems typically include at least a vector signal generator (VSG) for providing a source signal to be transmitted to the device, and a vector signal analyzer (VSA) for analyzing signals generated by the device. . The signals generated by the VSG and the analysis performed by the VSA are typically programmable so that signals of different frequency ranges, bandwidths, and signal modulation characteristics can be used to test whether various devices follow various wireless technology standards.

The calibration of the device under test (DUT) and the performance verification test are typically performed using a conductive signal path, such as a cable, rather than using a wireless signal path through which the DUT communicates with the tester via electromagnetic radiation. Accordingly, the signal between the tester and the DUT is carried via the conductive signal path rather than radiating outward through the surrounding space. The use of these conductive signal paths helps to ensure repeatability and consistency of the measurements, and eliminates the need to consider the positioning and orientation of the DUT in signal loading (transmission and reception).

For a multiple input multiple output (MIMO) DUT, each input/output of the device under test (DUT) must provide a certain type of signal path. For example, for a MIMO device intended to operate with three antennas, three conductive signal paths, such as cables and connections, must be provided for testing.

However, due to the need to physically connect and disconnect the device under test (DUT) and test Cables between the devices, so using a conductive signal path significantly affects the test time required for each DUT. Moreover, for a MIMO DUT, multiple connections and disconnections are required at the beginning of the test and termination of the test. Moreover, since the signal carried during the test is not via ambient radiation (the manner in which the signal is typically employed) and the antenna assembly of the device under test (DUT) is not used during such testing, such testing The real world operation is not simulated, and the test results do not reflect any performance characteristics belonging to the antenna.

Alternatively, testing can be performed using test signals carried via electromagnetic radiation rather than via cable conduction. This method has the advantage of not requiring connection and disconnection of the test cable, thereby shortening the test time associated with the connection and disconnection. However, due to the electromagnetic signals originating from other places and scattered around the surrounding space, the "channel" (ie, the surrounding space through which radiation and receiving test signals) existing in the radiated signal and the receiver antenna is inherently susceptible to signal interference and error. The device under test (DUT) antenna receives the signals and may include multipath signals from the various interfering signal sources due to signal reflections. Accordingly, the "conditions" of the "channel" are generally poor compared to the use of individual conductive signal paths (e.g., cables for each antenna connection).

One method of preventing or at least significantly reducing interference from such external signals is to use a shielded enclosure to isolate the radiation signal interface of the device under test (DUT) and the tester. However, such enclosures typically do not produce comparable measurement accuracy and repeatability. This can occur especially when the outer casing is smaller than the smallest echo-free chamber. Moreover, the enclosures tend to be sensitive to the location and orientation of the device under test (DUT) and are also sensitive to constructive and destructive interference of multipath signals generated within the enclosures.

Accordingly, it would be desirable to have a system and method for testing a wireless signal transceiver, particularly a wireless MIMO signal transceiver, in which a radiated electromagnetic test signal can be used, thereby Simulate real-world system operation and avoid the test time required to connect and disconnect test cables while maintaining test repeatability and accuracy by avoiding interference signals due to externally generated signals and multipath signal effects .

According to the invention of the present application, it provides a method for facilitating transmission and reception of a radio frequency (RF) signal A system and method for wireless testing of a device under test (DUT). Multiple radio frequency (RF) test signals generated from radio frequency (RF) test signals radiated from the device under test (DUT) can be captured using multiple antennas located within a shielded enclosure containing the device under test (DUT) And causing their individual signal phases to be controlled according to one or more signal characteristics, including ones of their individual signal power levels, the individual signal phases when they are received, and one of the received signals A combined signal power level. The phase control of the captured radio frequency (RF) test signal can be performed individually for any tested device under test (DUT) located within the shielded enclosure, thereby providing for the shielded enclosure to be unrelated to the device under test (DUT) The multipath signal environment is placed and compensated, and a wired test signal path is simulated in the wireless test of the device under test (DUT).

In accordance with an embodiment of the present invention, a system for facilitating wireless testing of a radio frequency (RF) signal transceiver device under test (DUT) includes: a structure defining an inner region and an outer region and configured to allow placement Placing a device under test (DUT) within the interior region and substantially isolating electromagnetic radiation originating from the outer region; a plurality of antennas at least partially disposed within the interior region for receiving with the device under test (DUT) At least one plurality of radio frequency (RF) test signals associated with a common radio frequency (RF) test signal radiated; and radio frequency (RF) signal control circuitry coupled to the plurality of antennas and responsive to the At least one plurality of radio frequency (RF) test signals: controlling at least a portion of the individual phases of the at least one plurality of radio frequency (RF) test signals according to the one or more phase control signals to provide at least one of a plurality of phase Controlling a radio frequency (RF) test signal, and measuring and combining the at least one plurality of phase controlled radio frequency (RF) test signals to provide the one or more phase control signals associated with the at least one plurality of phase controlled radio frequencies ( A radio frequency (RF) output signal combined with one of the RF) test signals.

In accordance with another embodiment of the present invention, a method of facilitating wireless testing of a radio frequency (RF) signal transceiver device under test (DUT) includes providing a structure defining an inner region and an outer region and configured Equivalently allowing a device under test (DUT) to be placed within the interior region and substantially isolating electromagnetic radiation originating from the outer region; providing a plurality of antennas at least partially disposed within the inner region for receiving and testing At least one plurality of radio frequency (RF) test signals associated with a common radio frequency (RF) test signal radiated by the device (DUT); and responsive to the at least one plurality of radio frequency (RF) test signals by: One or more phase control signals for controlling at least a portion of the individual phases of the at least one plurality of radio frequency (RF) test signals to provide at least one plurality of phase controlled radio frequency (RF) test signals, and measuring and combining the At least one plurality of phase controlled radio frequency (RF) test signals to provide the one or more phase control signals and one of the at least one plurality of phase controlled radio frequency (RF) test signals A radio frequency bonding (RF) output signal.

10‧‧‧ Controller

11a, 11b‧‧‧Wired signal interface

20‧‧‧ diagonal matrix

20a‧‧‧Matrix

22‧‧‧ diagonal

24a, 24b‧‧‧cross-coupling coefficient

100‧‧‧Tester

100a‧‧‧Tester

102‧‧‧Antenna

102a, 102b, 102n‧‧‧ tester antenna

102aa, 102ab, 102am, 102ba, 102bm‧‧‧ antenna elements

103a‧‧‧RF (RF) test signal

103ai‧‧‧main incident signal component

103aa, 103ab, 103am, 103bb, 103ba‧‧‧ signals

103br,103cr‧‧‧reflected signal component

104‧‧‧Conductive signal connector

104a, 104b, 104n‧‧‧ tester connector

105a, 105b, 105n‧‧‧ test signals

106‧‧‧RF (RF) coaxial cable

106a, 106b, 106n‧‧‧ test cable

107‧‧‧Test connection

107a‧‧ Channel

110, 110a, 110b, 110n‧‧‧ signal source

111, 111a, 111b, 111n‧‧‧ radio frequency (RF) test signals

130,130a,130b‧‧‧RF signal control circuit

131aa, 131ab, 131am‧‧‧ radio frequency (RF) test signals

132‧‧‧Signal size control circuit

133‧‧‧ test signal

135a, 135b, 135m‧‧‧ radio frequency (RF) test signal

136, 136a, 136b, 136m‧‧‧ phase control circuit

137,138‧‧‧Control circuit

139a, 139b, 139m‧‧‧ control signals

150‧‧‧ Radio Frequency (RF) Signal Control Circuit

152‧‧‧ Circuitry

152a, 152b‧‧‧ phase control components

155a‧‧‧ feedback signal

155b‧‧‧ signal

200,200a‧‧‧Device under test (DUT)

201a, 201aa‧‧‧Return data

202,202a,202b,202n‧‧‧Antenna

203‧‧‧radiating electromagnetic signals/signals

203a‧‧‧Device under test (DUT) signal

203b, 203c‧‧‧ signal components

203br, 203cr‧‧‧ reflected signal component

203ai‧‧‧main incident signal component

203i‧‧‧incident signal component

203r‧‧‧reflected signal component

204‧‧‧Conductive signal connector

204a, 204b, 204n‧‧‧Device under test (DUT) connector

207ap, 207bp‧‧‧ phase control signal

210, 210a, 210b, 210n‧‧‧ Radio Frequency (RF) Signal Receiver

211‧‧‧Communication test signal

211a, 211b, 211n‧‧‧ radio frequency (RF) test signals

300,300b‧‧‧Shielded enclosure

301‧‧‧Internal

301a, 301b‧‧‧Internal area

301d‧‧‧ end face

302,304,306‧‧‧Internal surface

320‧‧‧ Radio Frequency (RF) Absorbent Materials

232, 232a, 232b‧‧‧ control signal gain stage

234‧‧‧Signal combining circuit

235‧‧‧Complex test signal

235a, 235b‧‧‧ antenna array

236a, 236b, 236c, 236d, 236e, 236g, 236h, 236i, 236j, 236k, 236l, 236m, 236n, 236o, 236p ‧ ‧ phase control circuit

237a, 237b, 237n‧‧‧ phase-controlled test signals

242‧‧‧Control system

242b‧‧‧Control circuit

242aa, 242ab, 242an, 243aa, 243ab, 243an‧‧‧ power measurement signals

242ca, 242cb, 242cn‧‧‧ phase detector

242d‧‧‧Control circuit

243a, 243b, 243n‧‧‧ power measurement signals

243ba, 243bb, 243bn‧‧‧ phase control signals

243ca, 243cb, 243cn‧‧‧ phase data

243da, 243dn, 243db‧‧‧ phase control signal

244‧‧‧Replacement of downstream control systems

244a‧‧‧Power measurement circuit

244b‧‧‧Control circuit

245a, 245b, 245n, 245ba, 245bb, 245bn‧‧‧ phase control signals

410,420,430,440‧‧‧Process

411,412,413,414,415,416,417,418,421,422,423,424,425,426,427,431,432,433,434,435,441,442,443,444,445,446,447,448,449,450,451‧‧

510‧‧‧Expanded

511‧‧‧frequency band

521‧‧‧ upper map

522, 523‧‧‧ response map

H11, h22, hnn‧‧ channel

H11, h12, h22, h21, h1n, h2n, hn1, hn2‧‧ channel

Figure 1 depicts a typical operation of a wireless signal transceiver and a possible test environment.

Figure 2 depicts a wireless signal transceiver test environment using a conductive test signal path.

3 depicts a MIMO wireless signal transceiver test environment using conductive signal paths and a channel model for such test environments.

4 depicts a MIMO wireless signal transceiver test environment using radiated electromagnetic signals and a channel model for such test environments.

FIG. 5 depicts a test environment in which an MIMO DUT can be tested using a radiated electromagnetic test signal in accordance with an exemplary embodiment.

Figure 6 depicts a test environment where the DUT is tested using a radiant electromagnetic test signal within the shielded enclosure.

7 and 8 depict an exemplary embodiment of a test environment for testing a wireless DUT using a radiated electromagnetic test signal within a shielded enclosure that reduces multipath signal effects.

Figure 9 depicts a physical representation of a shielded enclosure in accordance with an exemplary embodiment for use in the test environment of Figures 7 and 8.

10 depicts a test environment in which a device under test (DUT) can be tested using a radiated electromagnetic test signal, in accordance with an illustrative embodiment.

11 depicts another test environment in which a device under test (DUT) can be tested using a radiated electromagnetic test signal, in accordance with an illustrative embodiment.

Figure 12 depicts an exemplary algorithm for testing a device under test (DUT) using the test environment of Figure 11.

13 depicts another test environment in which a device under test (DUT) can be tested using a radiated electromagnetic test signal, in accordance with an illustrative embodiment.

Figure 14 depicts an exemplary algorithm for testing a device under test (DUT) using the test environment of Figure 13.

15 depicts another test environment in which a device under test (DUT) can be tested using a radiated electromagnetic test signal, in accordance with an illustrative embodiment.

Figure 16 depicts an exemplary algorithm for testing a device under test (DUT) using the test environment of Figure 15.

17 depicts a test signal transmitted over a defined frequency range by a device under test (DUT) prior to compensation, in accordance with an exemplary embodiment.

18 depicts the scan test signal of FIG. 17 before and after compensation, and the exemplary phase shift values of the test environment of FIGS. 10, 11, 13, and 15 in accordance with an exemplary embodiment.

Figure 19 depicts an exemplary algorithm for performing the compensation as described in Figure 18.

20 depicts another test environment for testing one wireless device under test (DUT) using multiple test signal phase shifts in accordance with an exemplary embodiment.

21 depicts the test environment of FIG. 20 with additional test signal gain adjustments for compensation, in accordance with an additional exemplary embodiment.

The following illustrative embodiments of the invention are described in detail with reference to the drawings. this The description is intended to be illustrative, and not to limit the scope of the invention. The embodiments are described in sufficient detail to enable those skilled in the art to practice the invention. It is understood that other embodiments may be practiced without departing from the spirit and scope of the invention.

Throughout the disclosure, the description may be understood without a clear indication to the contrary. The individual circuit components can be singular or plural in number. For example, the terms "circuit" and "circuitry" may include a single element or a plurality of elements, which may be active and/or passive, and connected or coupled together (for example, as One or a plurality of integrated circuit chips) to provide the described functionality. In addition, the "signal" can refer to one or more currents, one or more voltages or data signals. In the drawings, similar or related elements may have similar or related alphanumeric or alphanumeric identifiers. Furthermore, although the invention has been discussed using discrete electronic circuitry (preferably in the form of one or a plurality of integrated circuit wafers), it may additionally be used depending on the frequency or data rate of the signal to be processed. One or more suitably programmed processors implement the functionality of any of the circuitry. Moreover, in the case of graphically illustrating functional block diagrams of various embodiments, the functional blocks are not necessarily indicative of the blocks between the hardware circuitry.

Please refer to Figure 1, a typical operating environment and ideal test of a wireless signal transceiver. The environment (at least in terms of real world operations) has a tester 100 and a device under test (DUT) 200 for wireless communication. Typically, some form of test controller 10 (e.g., a personal computer) will also be used to exchange test commands and data with tester 100 and device under test (DUT) 200 via wired signal interfaces 11a, 11b. Tester 100 and device under test (DUT) 200 each have one (for MIMO devices, multiple) respective antennas 102, 202, by conductive signal connectors 104, 204 (eg, coaxial cable connections, many of which are The tester 100 and the device under test (DUT) 200 are connected as is known in the art. Test signals (sources and responses) are wirelessly carried between the tester 100 and the device under test (DUT) 200 via antennas 102, 202. For example, DUT antenna 202 may radiate electromagnetic signal 203 during a transmission (TX) test of device under test (DUT) 200. Depending on the directionality of the antenna's transmit field type, this signal 203 will radiate in many directions, causing the tester antenna 102 to receive The incident signal component 203i and the reflected signal component 203r. As described above, these reflected signal components 203r, which are typically multipath signal effects and products originating from electromagnetic signals elsewhere (not shown), cause constructive interference and destructive signal interference, thus impeding reliable Repeatable signal reception and test results.

Please refer to Figure 2. To avoid these unreliable test results, use a conductive signal path. A path (such as RF coaxial cable 106) is used to connect tester 100 and antenna connectors 104, 204 of device under test (DUT) 200 to provide consistent, reliable between tester 100 and device under test (DUT) 200. And a repeatable conductive signal path to carry the test signal. As noted above, however, the time required to connect and disconnect the cable 106 before and after testing can extend the overall test time.

Please refer to FIG. 3, when testing the MIMO device under test (DUT) 200a, The extra test time for connecting and disconnecting the test cable is even longer. In such cases, multiple test cables 106 are required to connect the corresponding tester 104 and device under test (DUT) 204 connectors to enable carrying RF signal source 110 (eg, VSG) from tester 100a. The RF test signal is received by the RF signal receiver 210 within the device under test (DUT) 200a. For example, in a typical test environment, a tester for testing a MIMO device will have one or more VSGs 110a, 110b, ..., 110n to provide corresponding one or more RF test signals 111a, 111b, ... 111n (eg, a packet data signal with variable signal power, packet content, and data rate). The corresponding test cables 106a, 106b, ..., 106n connected via respective tester connectors 104a, 104b, ..., 104n and DUT connectors 204a, 204b, ..., 204n carry these signals so as to be received The RF test signals 211a, 211b, ..., 211n are provided to corresponding RF signal receivers 210a, 210b, ..., 210n within the device under test (DUT) 200a. Accordingly, the additional test time required to connect and disconnect these test cables 106 can be increased by n times, which corresponds to n times. The number of cables 106 is tested.

As described above, the test cable using the connection tester 100a and the device under test (DUT) 200a does have the advantage of providing a consistent, reliable, and repeatable test connection. As is known to those skilled in the art, the test connections 107 can be modeled as a signal channel H characterized by a pair of angular matrices 20, wherein the diagonal matrix elements 22 correspond to channel characteristics for the individual signals (eg, The direct-coupling coefficients h ₁₁ , h ₂₂ , . . . , h _nn (h _ij , where i=j) of the signal path conductance or loss of the individual test cable 106.

Referring to FIG. 4, in accordance with one or more exemplary embodiments, a conductive (or wired) channel 107 is replaced by a wireless channel 107a corresponding to the wireless signal interface 106a between the tester 100a and the device under test (DUT) 200a (FIG. 3). ). As described above, tester 100a and device under test (DUT) 200a communicate test signals 111, 211 via respective arrays of antennas 102, 202. In this type of test environment, the pair of angular matrices 20 are not used to represent the signal channel 107a, but the diagonal 22 is removed using one or more non-zero cross-coupling coefficients 24a, 24b (h _ij , where i ≠ j) A matrix 20a represents the signal channel 107a. It will be readily apparent to those skilled in the art that this is due to the plurality of available wireless signal paths in channel 107a. For example, unlike cable signal environments, each DUT connector 204 desirably receives only signals from its corresponding tester connector 104. In this wireless channel 107a, the first DUT antenna 202a receives test signals radiated by all of the tester antennas 102a, 102b, ..., 102n, for example, corresponding to channel matrix H coefficients h ₁₁ , h ₁₂ , ..., and h _1n .

According to conventional principles, the coefficient h of the channel matrix H corresponds to the characteristics of the channel 107a, which affects the transmission and reception of the RF test signal. These coefficients h jointly define the channel condition number k(H), which is the product of the norm of the H matrix and the norm of the inverse matrix of H, as expressed by the following equation: k(H)=||H||*| |H ^-1 ||

Factors affecting these coefficients change the number of channel conditions and thus the measurement error. For example, in a poorly qualified channel, small errors can cause large errors in the test results. In the case of a low number of channels, small errors in the channel can produce small measurement errors at the receiving (RX) antenna. However, in the case where the number of channels is high, a small error in the channel can cause a large measurement error at the receiving antenna. This channel condition number k(H) is also sensitive to the positioning and orientation of the physical DUT within its test environment (e.g., shielded enclosure) and the orientation of its various antennas 204. Accordingly, even if there is no external interference signal originating from other places or re-incident to the receiving antenna 204 via reflection, the possibility of repeating the accurate test result is still low.

Referring to FIG. 5, in accordance with one or more exemplary embodiments, the test signal interface between the tester 100a and the device under test (DUT) 200a may be wireless. A device under test (DUT) 200a is disposed within the interior 301 of the shielded enclosure 300. The shielded outer casing 300 can be implemented as a metal outer casing, for example, constructed or at least similar in effectiveness to a Faraday cage. This isolates the device under test (DUT) 200a from radiation signals originating from the outer region 302 of the outer casing 300. According to an exemplary embodiment, the geometry of the outer casing 300 is such that it acts as a closed waveguide.

Elsewhere, for example, a plurality (n) of antenna arrays 102a, 102b, ..., 102n are disposed within or opposite the inner surface 302 of the outer casing 300, each of which radiates a test originating from the tester 100a A plurality of phase controlled RF test signals 103a, 103b, ..., 103n of signal sources 110a, 110b, ..., 110n (discussed in more detail below). Each antenna array contains more (M) antenna elements. For example, the first antenna array 102a includes m antenna elements 102aa, 102ab, ..., 102am. The respective phase-controlled RF test signals 131aa, 131ab, ..., 131am provided by the respective RF signal control circuits 130a drive each of these antenna elements 102aa, 102ab, ..., 102am.

As described in the example of the first RF signal control circuit 130a, by means of a large signal A signal magnitude control circuit 132 increases (e.g., amplifies) or reduces (e.g., attenuates) the magnitude of the RF test signal 111a from the first RF test signal source 110a. The size controlled test signal 133 is copied by a signal replica circuit 134 (e.g., a signal divider). The respective signals of the size-controlled and replicated RF test signals 135a, 135b, ..., 135m are phase controlled (e.g., shifted) by respective phase control circuits 136a, 136b, ..., 136m to produce a size and phase controlled signal 131aa 131ab, ..., 131am drive the antenna elements 102aa, 102ab, ..., 102am of the antenna array 102a.

By the corresponding RF signal control circuits 130b, ..., 130m in a similar manner The remaining antenna arrays 102b, ..., 102n and their respective antenna elements are driven. This generates a corresponding number of composite radiation signals 103a, 103b, ..., 103n, which are carried and received by antennas 202a, 202b, ..., 202n of the device under test (DUT) 200a, according to the channel matrix H, as described above . The device under test (DUT) 200a processes its corresponding received test signals 211a, 211b, ..., 211m and provides one or more feedback signals 201 indicative of the characteristics (e.g., size, relative phase, etc.) of the received signals. These feedback signals 201a are provided to a control circuit 138 within the RF signal control circuit 130. This control circuit 138 provides control signals 137, 139a, 139b, ..., 139m for the size control circuit 132 and the phase control circuit 136. Accordingly, a closed loop control path is provided to gain and phase control the radiated signal from the tester 100a to enable the device under test (DUT) 200a to Receive this signal. (Alternatively, this control circuit 130 can be included as part of the tester 100a).

Control circuit 138 is used from the device under test according to conventional channel optimization techniques. The feedback data 201a of the (DUT) 200a changes the magnitude and phase of the radiated signal in a manner similar to minimizing the channel condition number k(H), achieving an optimal channel condition and producing an approximate channel as measured at each DUT antenna 202. Equally received signals. This will establish a communication channel through which the radiation signal produces a test result that substantially rivals the test results produced using a conductive signal path (eg, an RF signal cable).

Controlling the power by RF signals after successive transmission and channel condition feedback events This operation of control circuit 138 of path 130 will change the signal magnitude and phase of each antenna array 102a, 102b, ..., 102n to achieve an optimized channel condition number k(H). Once the optimized channel condition number k(H) has been achieved, the corresponding size and phase settings can be retained, and the tester 100a and the device under test (DUT) 200a can continue the subsequent test sequence, as in the cable. The line test environment does the same.

In practice, a reference DUT is placed in a test clip within the shielded housing 300. Used to optimize the channel conditions through the repeated procedures described above. Thereafter, the further DUT of the same design can be tested sequentially without the need to perform channel optimization in all of the instances, since the path loss encountered in the channel environment controlled by the enclosure 300 should be properly within the normal test tolerance.

Still referring to FIG. 5, for example, the model is initially transmitted to generate a channel condition number of 13.8 db, and the magnitudes of the h ₁₁ and h ₂₂ coefficients are -28 db and -28.5 db, respectively. The size matrix of channel H will be expressed as follows:

After resizing and phase, as described above, the channel condition number k(H) is reduced to 2.27 db, and the h ₁₁ and h ₂₂ coefficients are -0.12 db and -0.18 db, respectively, and the following channel size matrix is generated. :

These results are comparable to the results of using a cable test environment, indicating that this wireless test environment provides comparable accuracy. Eliminating the time of connecting and disconnecting the signal path of the cable, and including the shortening of the size and phase adjustment, the overall received signal test time is significantly shortened.

Please refer to Figure 6 for a better understanding of the effects of multipath signal effects on channel conditions. As described above, once the device under test (DUT) 200a is placed within the interior 301 of the housing 300, the device under test (DUT) 200a will radiate the electromagnetic signal 203a from each antenna 202a during the transmission test. This signal 203a contains components 203b, 203c that are radiating outwardly and away from the antenna 102a of the tester 100a. However, these signal components 203b, 203c are reflected off the inner surfaces 304, 306 of the outer casing 300 and are incident as reflected signal components 203br, 203cr, and constructively or destructively combined with the main incident signal component 203ai in accordance with multipath signal conditions. . As mentioned above, depending on the constructive and destructive nature of the interference, the test results used in proper calibration and performance verification will It tends to be unreliable and inaccurate.

Referring to FIG. 7, in accordance with an exemplary embodiment, RF absorber material 320a, 320b is disposed at reflective surfaces 304, 306. As a result, the reflected signal components 203br, 203cr are significantly attenuated, resulting in less constructive or destructive interference to the primary incident signal component 203ai.

Additional RF signal control circuit 150 can be included to be in antenna array 102a and tested Used between the devices 100a, the antenna array 102a is mounted within or on the interior 301 of the housing 300a. (Alternatively, this additional control circuit 150 can be included as part of the tester 100a). The radiation signals incident on the antenna elements 102aa, 102ab, ..., 102am generate received signals 103aa, 103ab, ..., 103am, wherein the respective signal phases are controlled (e.g., shifted) by the phase control circuit 152, the phase control circuit 152 Phase control elements 152a, 152b, ..., 152m are controlled in accordance with one or more phase control signals 157a, 157b, ..., 157m provided by control system 156. The resulting phase controlled signals 153 are combined in a signal combiner 154 to provide the received signal 155a to the tester 100a and a feedback signal 155b to the control system 156. Control system 156, which is part of a closed-loop control network, processes this feedback signal 155b to adjust the respective phases of composite received signals 103aa, 103ab, ..., 103am as needed to minimize the table associated with internal region 301 of housing 300a. Observe the signal path loss. In the case of changing the position and orientation of the device under test (DUT) 200a within the housing 300a, the closed-loop control network also allows the system to reconfigure the phased array enabled by the antennas 102a and phase control circuit 152. As a result, after minimizing the path loss using this feedback loop, it is achieved that the DUT signal 203a is accurately and reproducibly loaded into the tester 100a using the radiated signal environment within the housing 300a.

Please refer to Figure 8 for the DUT receiving signal test to achieve accurate and Repeat similar control and improvement of test results. In this case, by signal combiner/separator 154 The test signal 111a provided by the tester 100a is copied, and if necessary, the phase of the replicated test signal 153 is adjusted by the phase control circuit 152 before being radiated by the antenna elements 102aa, 102ab, ..., 102am. As in the foregoing case, the reflected signal components 103br, 103cr are significantly attenuated, thereby creating less constructive or destructive interference to the primary incident signal component 103ai. One or more feedback signals 203a from the device under test (DUT) 200a provide information needed to control the phase of the replicated test signal 153 to the control system 156 to minimize the apparent signal path associated with the interior 301 of the housing 300a. Loss, thereby establishing a consistent and repeatable condition of signal path loss.

Referring to FIG. 9, in accordance with one or more exemplary embodiments, substantially as shown The shield case 300b is implemented. As described above, the DUT can be positioned at one end 301d of the interior 301 of the housing 300b, which is opposite the interior region 301b, which contains or faces the interior surface of the tester antenna arrays 102a, 102b, ..., 102n. 302 (Figure 5). Located therebetween is an inner region 301a surrounded by a RF absorber material 320 that is formed by a waveguide chamber.

Illustrative implementation of systems and methods in accordance with the present invention, as described above and with the following details For example, the cable-free test of the wireless device under test (DUT) can be performed simultaneously with multipath effect compensation and optimized signal path loss control. Multiple antennas, and an antenna array, with a control system that can be used to adjust the phase of the test signal provided to the antenna element, emulating the stable and repeatable signal path loss typically associated with a conductive signal path environment Environment, using a radiation signal environment inside a shielded enclosure. At the same time, the time required to adjust the phase shifter is part of all of the overall test time, which is significantly less than the time required to connect and disconnect the test cable, and can provide realism including the antenna component Additional benefits of world testing.

Furthermore, as described above and further details below, the exemplary embodiments of the present invention provide Cableless testing of wireless device under test (DUT) using signals with a wide bandwidth (eg, 160 megahertz (MHz) wide signal as described in the Electrical Engineering of Electrical and Electronic Engineering (IEEE) standard 802.11ac) Test the same amount of test accuracy and measurement repeatability with a conductive signal path (eg test cable). The wideband signal received within the shielded test enclosure produces a substantially flat signal response by adjusting the phase of the test signal provided to the antenna element. Once the individual test signal phases that drive the individual antenna elements are adjusted to produce this flat signal response environment, the test using the wideband signals can be performed directly without further adjustments, as in a cabled test environment. While the location of the device under test (DUT) within the shielded enclosure can affect the flatness of the channel response, this location sensitivity is within the measurement tolerances described in the signal standard (eg, IEEE 802.11ac).

Moreover, according to an exemplary embodiment, multiple measurements within the same shielded enclosure The device (DUT) can perform this cableless test at the same time. By properly controlling and adjusting the phase and magnitude of the test signal driving the multiple antenna elements, a radiation test signal environment within the shielded enclosure can be used to mimic the low crosstalk interference signal environment of the conducted signal path. Once the phase and gain (or attenuation) of the test signal driving the antenna element are adjusted in accordance with the exemplary embodiment, the signal received by the antenna of the multiple device under test (DUT) will be received using the cable signal path. The signal is equal. For example, this can be achieved by maximizing the direct-coupling coefficient of the channel matrix while minimizing the cross-coupling coefficients of the channel matrix (eg, producing a difference of at least 10 dB between the direct-and cross-coupling coefficients).

Referring to FIG. 10, a device under test (DUT) 200a is in accordance with an exemplary embodiment. Located within the shielded enclosure 300 for transmitting signal testing. The test signal 203a transmitted via the antenna 202a of the device under test (DUT) is connected by multiple antenna elements 102a, 102b, ..., 102n Received. The individual signal phases of the generated received signals 105a, 105b, ..., 105n are controlled and adjusted by individual phase control circuits 236a, 236b, ..., 236n.

According to some exemplary embodiments, the generated phase controlled test signal 237a, 237b, ..., 237n are sent to a control system 242 (described in further detail below) and signal combining circuit 234. The control system 242 provides phase control signals 243a, 243b, ..., 243n to the phase control circuits 236a, 236b, ..., 236n. The combined (e.g., summed) phase controlled test signals 237a, 237b, ..., 237n generate a composite test signal 235 for downstream analysis, such as a VSA (not shown).

According to other embodiments, phase controlled test signals 237a, 237b, ..., 237n The combination is coupled in signal combiner 234 to produce a composite test signal 235. The composite test signal 235 is sent to an alternate control system 244 (described in further detail below) which then provides phase control signals 245a, 245b, ..., 245n to the phase control circuits 236a, 236b, ..., 236n.

Referring to Figure 11, in accordance with an exemplary embodiment, the inline control system 242 includes Power measurement circuits 242aa, 242ab, ..., 242an for measuring individual power levels of phase controlled test signals 237a, 237b, ..., 237n. The resulting power measurement signals 243aa, 243ab, ..., 243an indicative of individual test signal power levels are provided to control circuitry 242b (e.g., in the form of a digital signal processor (DSP)), which then provides appropriate phase control signals 243ba, 243bb, ..., 243bn are given to phase control circuits 236a, 236b, ..., 236n.

Referring to FIG. 12, the operation of the test environment of FIG. 11 is performed according to an exemplary embodiment. Mode 410 can be performed as shown. First, the phase shifters 236a, 236b, ..., 236n are initialized in step 411, for example, setting all phase shift values to a same reference phase value or individual reference phase values. Next, the phase controlled signals 237a, 237b, ..., 237n are measured in step 412. Power level. Then, the measured power value is summed in step 413, and the accumulated measured signal power and a previously accumulated measured signal power are compared in step 414. In step 415, if the current cumulative measured power is higher than the previous accumulated measured power, the current phase shift value and the accumulated measured power are stored, and then the stored values are compared with the expected criterion (eg, one in step 416). Maximize cumulative measurement power). In step 417, if the criterion is met, the adjustment of the phase of the test signal is stopped. If not, continue to adjust the phase of the test signal.

Similarly, in step 414, if the current cumulative measured power is not higher than the first If the measured power is accumulated before, the test signal will continue to be adjusted. Therefore, in step 418, the phase shifters 236a, 236b, ..., 236n are adjusted according to, for example, a genetic algorithm (GA) or a particle swarm optimization algorithm (PSA) to give received test signals 105a, 105b, ..., 105n A combination or permutation of another phase shift value. After this step, the power measurement 412 is repeated, summed 413 and compared 414 until the desired criterion is met.

Referring to Figure 13, in accordance with another exemplary embodiment, the alternate downstream control system 244 (FIG. 10) includes power measurement circuitry 244a (eg, a VSA) and control circuitry 244b (eg, a digital signal processor (DSP)). The power level of the composite signal 235 is measured by the power measurement circuit 244a to provide power measurement data 245a to the control circuit 244b. Control circuit 244b then provides appropriate phase control signals 245ba, 245bb, ..., 245bn to phase shifters 236a, 236b, ..., 236n.

Referring to FIG. 14, the operation mode 420 of the test environment in FIG. 13 can be as shown. Show. First, in step 421, phase shifters 236a, 236b, ..., 236n are initialized by setting one or more individual phase shift values in advance. Next, in step 422, the power level of the composite signal 235 is measured, and then in step 423, the current measured power and a previous measured power are compared. Rate level. In step 424, if the current measured power level is higher than the previous measured power level, the current phase shift value and the measured power are stored, and used in step 425 to determine whether the desired criterion has been met (eg, one Maximize measurement power level). In step 426, if the desired criterion is met, the phase adjustment is stopped. If the desired criterion is not met, the phase is continuously adjusted.

Similarly, if the current measured power is not higher than the previously measured power, continue Adjust the phase. Thus, phase shifters 236a, 236b, ..., 236n are adjusted according to an optimization algorithm (e.g., a GA or PSA) to give another set of phase shift values for receiving test signals 105a, 105b, ..., 105n.

Referring to Figure 15, the in-line system is in accordance with another exemplary embodiment. 242 (Fig. 10) includes phase detection circuits 242ca, 242cb, ..., 242cn and control circuit 242d (e.g., a DSP). The phase detectors 242ca, 242cb, ..., 242cn can detect the individual signal phases of the phase controlled signals 237a, 237b, ..., 237n and provide corresponding phase data 243ca, 243cb, ..., 243cn to the control circuit 242d. Based on this information, control circuit 242d provides appropriate phase control signals 243da, 243db, ..., 243dn to phase shifters 236a, 236b, ..., 236n.

Referring to FIG. 16, the operation mode 430 of the test environment in FIG. 15 can be as shown. Show. First, in step 431, phase shifters 236a, 236b..., 236n are initialized by giving one or more individual phase shift values. Next, in step 432, the individual phases of the phase controlled signals 237a, 237b, ... 237n are measured (e.g., relative to an identical or reference signal phase).

Then, according to the measured test signal phase, according to the best in step 433 The phase shift value is set to adjust the phase adjustment of the phase shifters 236a, 236b, ..., 236n. After this step, in step 434, the power level of the composite signal 235 is measured to confirm that the desired composite signal power level is reached, and then the phase adjustment is stopped in step 435.

Referring to Figure 17, a broadband day from a constant power device (DUT) 200a The exemplary received signal 203 emitted by line 202a radiates a good response in the frequency range of 700 to 6000 MHz within shielded enclosure 300 (e.g., Figure 6), as substantially shown in the figure. It can be clearly understood that the power profile is not flat based on the rich multipath signal environment within the shielded enclosure 300. For example, a packet data signal that communicates according to the IEEE standard 802.11ac is used, with a particular focus on a 160 MHz wide frequency band between 5000 and 5160 MHz. As shown, within this frequency band 511 (as indicated by the enlarged portion 510 of the signal 203 profile), the received signal exhibits a power variation of approximately 25 decibels (dB). According to an exemplary embodiment, using the test environment as described above and using a multiple phase shifter to control the phase of the test signal used to drive the multiple antenna elements, the present map may be compensated such that the focused frequency band 511 is substantially flat.

Referring to FIG. 18, according to an exemplary embodiment, this object can be used by using multiple instances. For example, 16) the antenna element 102 is implemented with a corresponding phase shifter 236. For example, an optimized flat response condition 523 may be achieved by using an optimization algorithm (further detailed below) and using only quadrature phase adjustments of 0, 90, 180, and 270 degrees. As shown, the response profile 522 has a variation of more than 5 dB between the 160 MHz bandwidth 511 of the exemplary test signal prior to compensation. Moreover, even if the antenna array has been optimized for power level at a frequency midpoint of 5080 MHz, as shown in the upper profile 521, the variation of the received signal is still about 5 decibels. However, when the multiple phase adjusters 236a, 236b, ..., 236p are appropriately adjusted, even if only the quadrature phase adjustment is limited, it is possible to achieve a response profile 523 having a variation of not more than 0.5 decibels.

Referring to Figure 19, the compensation shown in Figure 18 can be accomplished by using the illustrated flow 440. To achieve. First, in step 441, a plurality of frequency values within the desired signal bandwidth are defined, and in step 442, a set of initial phase shift values for the phase shifter is defined. Yubu In step 443, the phase shifter is set using the defined phase value, and in step 444, the power of each frequency is measured. Next, in step 445, the difference between the measured powers of the plurality of pairs of defined frequencies is calculated, and in step 446, the sum is used to evaluate a function F which is equal to between the defined maximum power difference and the calculated power plus total difference. The difference.

If the current calculation function F is greater than a previous operation of _{the current} function of _{the old F,} the phase shifter is retained values in Step 448, and the decision in step 449 satisfies a desired condition (e.g., to achieve a maximization operation function F ). If so, the phase adjustment is stopped at step 450. If the desired criterion is not met, the phase is continuously adjusted. Similarly, if the current calculation function F is not greater than a previous operation of _{the current} function of _{the old} F, continue adjusting the phase. In step 451, the phase is further adjusted by defining another set of values of the phase shifter values, and the phase adjustment step 443, the measurement power step 444, the operational power difference step 445, and the evaluation of the operational function F step 446 are repeated. . This process is repeated until the condition is met in step 449.

Referring to FIG. 20, when performing multiple wireless devices under test, according to an exemplary embodiment Similar compensation can be achieved in the case of a cableless test (DUT) where a cross-coupled signal is used within the shielded enclosure 300. (For the purposes of this example, two antenna arrays 235a, 235b are used for testing of the two devices under test (DUT) 200a, 200b. However, it will be apparent that other numbers of devices under test and antenna arrays may be used herein. It should be clearly understood that the respective "device under test (DUT)" 200a, 200b described herein can be an individual receiver within a single MIMO device (DUT) 200.) As described above, the source (eg, , VSG) 110 may provide test signal 111 and replicate with signal distributor 234 to provide a copy of test signal 235 for phase shifting by multiple phase shifter 231 to drive antenna element 102 of antenna array 235. . The antenna arrays 235a, 235b provide radiation signal components 103aa, 103ab, 103ba, 103bb corresponding to the frequency Direct-coupling and cross-coupling coefficients of the track matrix H (eg, as described above). The signal components 103aa, 103ab, 103ba, 103bb are received by the antennas 202a, 202b of the devices under test (DUT) 200a, 200b. The received signal data 201a, 201b is provided by the device under test (DUT) 200a, 200b to a control system 206 (e.g., a DSP), which then provides appropriate phase control signals 207ap, 207bp to phase shifters 236aa, ..., 236am, 236ba. , ..., 236bm, for controlling the phase of the signal radiated by the antenna elements 102aa, ..., 102am, 102ba, ... 102bm of the antenna arrays 235a, 235b.

By adjusting the phase of the radiation signal repeatedly, as described above, the straightness can be maximized The cross-coupling channel matrix H coefficients 103aa, 103ba are minimized and the cross-coupling coefficients 103ab, 103bb are minimized (e.g., by making the resulting cross-coupling coefficient ideally become at least 10 decibels below the direct-coupling coefficient).

Referring to FIG. 21, according to another exemplary embodiment, control system 206 may be further The steps are configured to provide gain control signals 207ag, 207bg to control the size of the replicated test signals 111a, 111b for transmission to the device under test (DUT) 200a, 200b. Control signal gain stages (e.g., variation gain amplifiers or signal attenuators) 232a, 232b can control the signal sizes. It may be advantageous to further optimize the relative size of the direct-coupling coefficients 103aa, 103ba and the cross-coupling coefficients 103ab, 103bb of the channel matrix H. For example, the size of the direct-coupling coefficients 103aa, 103ba can be normalized while still retaining sufficient cross-coupling coefficients 103ab, 103bb attenuation (eg, 10 decibels or higher).

Various other modifications and alterations of the present invention will be apparent to those skilled in the art without departing from the scope of the invention. Although the invention has been described in terms of specific preferred embodiments, it should be understood that the invention should not be The locality is limited to the preferred embodiment. The scope of the present invention and the structures and methods within the scope of the claims are intended to cover the equivalent of the structures and methods.

Claims (18)

An apparatus comprising a system for facilitating wireless testing of a radio frequency (RF) signal transceiver device under test (DUT), comprising: a structure defining an inner region and an outer region and configured to allow placement a device under test (DUT) in the inner region and substantially isolating electromagnetic radiation originating from the outer region; a plurality of antennas at least partially disposed within the inner region for receiving and receiving the device under test (DUT) Transmitting at least one plurality of radio frequency (RF) test signals associated with a common radio frequency (RF) test signal, and transmitting another plurality of radio frequency (RF) test signals to the device under test (DUT), Wherein the received and transmitted radio frequency (RF) test signals are received and transmitted through the same antenna of the plurality of antennas; and a radio frequency (RF) signal control circuit coupled to the plurality of antennas Responding to the at least one plurality of radio frequency (RF) test signals in accordance with one or more phase control signals for controlling at least a portion of the individual phases of the at least one plurality of radio frequency (RF) test signals to provide At least one plurality of phase controlled radio frequency (RF) test signals, measuring and combining the at least one plurality of phase controlled radio frequency (RF) test signals to provide the one or more phase control signals associated with the at least one plurality a radio frequency (RF) output signal combined with one of a phase controlled radio frequency (RF) test signal, and repeating the control and the measuring and combining until at least one of the following lists reaches a maximum signal power: the at least one plurality The cumulative power of the phase controlled radio frequency (RF) test signal, and the radio frequency (RF) output signal; The radio frequency (RF) signal control circuit provides the radio frequency (RF) output signal through a conductive signal path for allowing a tester to receive signals directly from the conductive signal path, and the internal region is included in the device under test ( The signal environment between the DUT and the tester is only an over-the-air (OTA) transceiver. The device of claim 1, wherein the radio frequency (RF) signal control circuit comprises: a phase control circuit coupled to the plurality of antennas and configured to provide the at least one plurality of phase controlled radio frequency (RF) test signals Responding to the at least one plurality of radio frequency (RF) test signals and the one or more phase control signals; a control signal circuit coupled to the phase control circuit and providing the one or more phase control signals, Responsive to the at least one plurality of phase controlled radio frequency (RF) test signals; and a combining circuit coupled to at least one of the phase control circuit and the control signal circuit, and by providing the radio frequency (RF) output signal, Responding to the at least one plurality of phase controlled radio frequency (RF) test signals. The device of claim 2, wherein the control signal circuit comprises a power detection circuit. The device of claim 2, wherein the control signal circuit comprises: a power measurement circuit that provides a plurality of individual power levels indicative of each of the at least one plurality of phase controlled radio frequency (RF) test signals a power signal responsive to the at least one plurality of phase controlled radio frequency (RF) test signals; and processing circuitry coupled to the power measurement circuit and responsive to the plurality of phase control signals by providing the one or more phase control signals Power signal. The device of claim 2, wherein the control signal circuit comprises a phase detection circuit. The device of claim 2, wherein the control signal circuit comprises: a phase measurement circuit responsive to the at least one plurality of phase controlled radio frequencies (RF) by providing a plurality of phase signals indicative of individual signal phases of each of the at least one plurality of phase controlled radio frequency (RF) test signals a test signal; and a processing circuit coupled to the phase measurement circuit and responsive to the plurality of phase signals by providing the one or more phase control signals. The device of claim 1, wherein the radio frequency (RF) signal control circuit comprises: a phase control circuit coupled to the plurality of antennas and configured to provide the at least one plurality of phase controlled radio frequency (RF) test signals Responding to the at least one plurality of radio frequency (RF) test signals and the one or more phase control signals; a combination circuit coupled to the phase control circuit and responsive to providing the radio frequency (RF) output signal At least one plurality of phase controlled radio frequency (RF) test signals; and a control signal circuit coupled to the combining circuit and the phase control circuit and responsive to the radio frequency (RF) by providing the one or more phase control signals )output signal. The device of claim 7, wherein the control signal circuit comprises a power detection circuit. The device of claim 7, wherein the control signal circuit comprises: a power measurement circuit responsive to the radio frequency (RF) output signal by providing a power signal indicative of a power level of the radio frequency (RF) output signal And a processing circuit coupled to the power measurement circuit and responsive to the power signal by providing the one or more phase control signals. A method of facilitating wireless testing of a radio frequency (RF) signal transceiver device under test (DUT), comprising: providing a structure defining an inner region and an outer region and configured to allow placement Depositing a device under test (DUT) within the interior region and substantially isolating electromagnetic radiation originating from the outer region; providing a plurality of antennas at least partially disposed within the inner region for receiving and receiving the device under test ( At least one plurality of radio frequency (RF) test signals associated with a common radio frequency (RF) test signal radiated by the DUT and used to transmit additional plurality of radio frequency (RF) test signals to the device under test (DUT) And wherein the received and transmitted radio frequency (RF) test signals are received and transmitted through the same antenna of the plurality of antennas; and the at least one plurality of radio frequency (RF) tests are responded to by: Signal: controlling at least a portion of the individual phases of the at least one plurality of radio frequency (RF) test signals according to one or more phase control signals to provide at least one of a plurality of phase controlled radio frequency (RF) test signals, and measuring Combining the at least one plurality of phase controlled radio frequency (RF) test signals to provide a combination of the one or more phase control signals in combination with one of the at least one plurality of phase controlled radio frequency (RF) test signals (RF) outputting the signal, and repeating the control and the measuring and combining until at least one of the following listed maximum signal powers: cumulative power of the at least one plurality of phase controlled radio frequency (RF) test signals, and a radio frequency (RF) output signal; wherein the radio frequency (RF) output signal is provided through a conductive signal path for allowing a tester to receive signals directly from the conductive signal path, and the internal region is included in the device under test ( The signal environment between the DUT and the tester is only an over-the-air (OTA) transceiver. The method of claim 10, wherein: The controlling includes responding to the at least one plurality of radio frequency (RF) test signals and the one or more phase control signals by providing the at least one plurality of phase controlled radio frequency (RF) test signals; and the measuring and combining Measuring the at least one plurality of phase controlled radio frequency (RF) test signals to provide the one or more phase control signals, and combining the at least one plurality of phase controlled radio frequency (RF) test signals to provide the radio frequency (RF) output signal. The method of claim 11, wherein the measuring the at least one plurality of phase-controlled radio frequency (RF) test signals comprises detecting at least one power of the at least one plurality of phase-controlled radio frequency (RF) test signals. The method of claim 11, wherein the measuring the at least one plurality of phase controlled radio frequency (RF) test signals comprises: detecting at least one power of the at least one plurality of phase controlled radio frequency (RF) test signals to Providing a plurality of power signals indicative of individual power levels of each of the at least one plurality of phase controlled radio frequency (RF) test signals; and processing the plurality of power signals to provide the one or more phase control signals. The method of claim 11, wherein the measuring the at least one plurality of phase-controlled radio frequency (RF) test signals comprises detecting at least one phase of the at least one plurality of phase-controlled radio frequency (RF) test signals. The method of claim 11, wherein the measuring the at least one plurality of phase-controlled radio frequency (RF) test signals comprises: detecting at least one phase of the at least one plurality of phase-controlled radio frequency (RF) test signals to provide a plurality of phase signals indicative of individual signal phases of each of the at least one plurality of phase controlled radio frequency (RF) test signals; and processing the plurality of phase signals to provide the one or more phase control signals. The method of claim 10, wherein the controlling comprises: providing the at least one plurality of phase controlled radio frequency (RF) test signals in response to the at least one plurality of radio frequency (RF) test signals and the one or more a plurality of phase control signals; and the combining and combining includes combining the at least one plurality of phase controlled radio frequency (RF) test signals to provide the radio frequency (RF) output signals, and measuring the radio frequency (RF) output signals to provide the One or more phase control signals. The method of claim 16, wherein the measuring the radio frequency (RF) output signal to provide the one or more phase control signals comprises detecting a power of the radio frequency (RF) output signal. The method of claim 16, wherein the measuring the radio frequency (RF) output signal to provide the one or more phase control signals comprises: detecting a power of the radio frequency (RF) output signal to provide an indication of the radio frequency (RF) a power signal that outputs a power level of the signal; and processing the power signal to provide the one or more phase control signals.